Bending back the biodiversity loss curve of sharks and rays. The loss of sharks and rays to date has involved serial depletion of the largest, most evolutionary and functionally distinct species, and the increasing prevalence of smaller-bodied species that have benefited from release from predation.

New paper out today in @natrevbiodiv.nature.com by the #GlobalSharkTrends team: Bending back the curve of shark & ray biodiversity loss;
Read the paper here: rdcu.be/eZ9n9
@sfu.ca
@sfubiosciences.bsky.social
@earth2ocean.bsky.social

Yesterday our new #globalsharktrends paper came out in @science.org
@nickdulvy.bsky.social did a great thread on the paper and included some GIFs that we had made but they did not play here on @bsky.app
I'm hoping this now works.
Status change through time...
science.org/doi/10.1126/...

New research from E2O's Dulvy Lab was published in Science yesterday. Check out the thread below!
#GlobalSharkTrends
#MarineScience
#SharksAndRays

La trajectoire actuelle du risque d'extinction entraîne une perte disproportionnée (22%) de la diversité fonctionnelle écologique des requins et des raies.

#GlobalSharkTrends
bit.ly/GlobalSharkT...

🧵13/21

La vague croissante du risque d'extinction des requins et des raies #GlobalSharkTrends
👉 a commencé dans les rivières, estuaires et eaux côtières proches
👉 avant de se propager rapidement à travers les océans.

🧵10/21

#GlobalSharkTrends
Depuis la rédaction de l'article, @SharkColin
a créé un second GIF fascinant de l'Indice de la Liste Rouge (RLI) pour les requins, raies et chimères.

🧵8/21

La #surpêche a divisé par deux les populations de poissons chondrichthyens – requins, raies, chimères – depuis 1970. Les pêcheries ciblées et la capture accidentelle (prises accessoires), ont conduit à plus d'un tiers des espèces menacées d'extinction.

🧵4/21
#GlobalSharkTrends

Nouvelle analyse #GlobalSharkTrends financée par @SharkRayFund
sert de signal d'alarme pour une action urgente afin d'inverser la tendance pour ces animaux extraordinaires!

🧵2/21
#surpêche

Nouvelle étude #GlobalSharkTrends publiée dans @ScienceMagazine révèle que la #surpêche a réduit de 50% les populations de requins et de raies en 50 ans, causant une érosion des fonctions écologiques et un risque d'extinction élevé.
Article : bit.ly/GlobalSharkT...
🧵1/21

Estuary Stingray feeding over soft sediment in Brisbane harbour, in new study that shows they are mobilising tonnes of sediment each year as they feed. By Molly Grew / Vincent Raoult

The current extinction risk trajectory is driving disproportionate (22%) loss of ecological functional diversity of sharks and rays.
www.science.org/doi/epdf/10....
#GlobalSharkTrends
bit.ly/GlobalSharkTrends
🧵13/20

The wave of rising shark & ray extinction risk #GlobalSharkTrends
👉 started in rivers, estuaries, nearshore coastal waters
👉 before rapidly expanding out across the oceans.
Lower risk only in harder-to-fish nearshore habitats, ie,
👉 Kelp/algal reefs
👉 Rocky reefs, &
👉 Deepsea
🧵10/20

#GlobalSharkTrends
Steep declines in largest and most functionally important shark and rays species, especially:
➡️ Rhino rays (sawfishes, giant guitarfishes, wedgefishes), devil & eagle rays
➡️ Hammerheads, requiem, angel and gulper sharks.
🧵9/20

Waffle plot of changing Red List Index status of sharks, rays and chimaeras BY HABITAT over past 50 years Credit Colin simpfendorfer

#GlobalSharkTrends
Since we wrote the paper @sharkcolin.bsky.social coded a mesmerizing GIF oif Shark & Ray Red List Index
by habitat
🧵8/20

Waffle plot of changing Red List Index status of sharks, rays and chimaeras over past 50 years by Colin Simpfendorfer

#GlobalSharkTrends
Since we wrote the paper @sharkcolin.bsky.social coded a mesmerizing GIF of the Red List Index for sharks, rays & chimaeras
🧵7/20

Sankey plot of Red List Status over time over Requiem sharks in black and white photo by Hannes Klostermann Ocean Image Bank

New global analysis, experts calculate aquatic RLI for 1,199 sharks, rays & chimaeras from 1970 to 2020.
👉 over 1/3 qualify as Critically Endangered, Endangered, Vulnerable
👉 Red List Index has worsened by 19% since 1970
#GlobalSharkTrends
bit.ly/GlobalSharkTrends
🧵6/20

A blue Shark (Prionace glauca) and an inset graph showing the Red List Indices for sharks and rays compared to other comprehensively assessed groups Credit Maite Erauskin-Extramiana

The Red List Index (RLI) is based on the @sscmarine.bsky.social
@iucnshark.bsky.social red list assessments & is widely used to report on status of terrestrial biodiversity & conservation, yet there is no equivalent for the oceans
#GlobalSharkTrends
bit.ly/GlobalSharkTrends
🧵5/20

A Bluntnose Sixgill Shark (Hexanchus griseus) off Puget Sound, United States. Photo by Greg Amptman.

Overfishing has halved populations of chondrichthyan fishes – sharks, rays, & chimaeras – since 1970. Target fisheries & incidental capture (bycatch) has resulted in over 1/3 threatened with extinction.
#GlobalSharkTrends
🧵4/20
#EndOverfishing
#SustainableDevelopmentGoals

A wobbegong image by Tom Fish (Pexels). These iconic sharks are sit-and-wait predators, mainly on or around coral reefs

Chondrichthyans are an ecologically diverse and ancient lineage of over 1,199 fishes that occur in a wide range of estuarine,marine, & even some freshwater habitats, dominating the higher trophic levels at the top of ecological pyramids
#SharkScience
#GlobalSharkTrends
🧵3/20

A whale Shark (Rhincodon typus) lit from above in a shoal of small fishes; IUCN Endangered © Emilie Ledwidge_Ocean Image Bank (2).jpg

New #GlobalSharkTrends analysis funded by @SharkRayFund serves as a #wakeupcall for urgent action to turn the tide for these extraordinary animals:
bit.ly/GlobalSharkTrends
🧵2/20
#EndOverfishing
#SustainableDevelopmentGoals

Scalloped hammerhead sharks (Sphyrna lewini) IUCN Critically Endangered © Masayuki Agawa_Ocean Image Bank

New #GlobalSharkTrends study published in @science.org reveals #overfishing has more than halved shark & ray populations over the past 50-years causing widespread erosion of ecological function and exceptionally high extinction risk
👉Full article bit.ly/GlobalSharkTrends
🧵1/20

Male skate (Fenestraja sp.) with attached parasitic isopod seen towards the beginning of the dive. Photo by NOAA Office of Ocean Exploration and Research.

#SharksintheDark: Increased use and trade in deepwater sharks and rays needs to be closely monitored and managed to avoid increasing extinction risk. 🦑🌍🐟
 
#ElevatetheSkate #GlobalSharkTrends
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Deepwater shark returned to the sea. Photo by Melissa Romao/Sea Shepherd.

To conserve deepwater sharks and rays, we need:
👉 To protect important areas
👉 National-level fisheries regulations
👉 Introduce trade controls
🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends #OceanOptimism
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Gulper Shark (Centrophorus granulosus) landed after being caught by deepwater fisheries operating off India. Photo by Ebeena Francis.

To conserve deepwater sharks and rays, we need:
👉 To protect important areas
👉 National-level fisheries regulations
👉 Introduce trade controls
🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends #OceanOptimism
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

A Bluntnose Sixgill Shark (Hexanchus griseus) off Puget Sound, United States. Photo by Greg Amptman

A global fishing prohibition below 800 m would provide 30% vertical refuge for 30% of threatened deepwater sharks and rays. 🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends #OceanOptimism
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Gulper shark (Centrophorus spp.) Photo by Andy Murch | www.sharksandrays.com

#PressRelease: Protecting 30% of the deep ocean would provide 80% of deepwater sharks and rays with refuge from human activities. Spatial protection in the High Seas is important for Date Deficient species.
🦑🌍🐟
 
#GlobalSharkTrends #30x30 bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Dried skate for sale at Jagalchi, the country's largest seafood market, located in Busan, south of Seoul. Photo by Marius Stankiewicz.

#ElevatetheSkate: Increased demand for skate meat has incentivized skate retention around the world, particularly for the fermented skate meat (hongeo-hoe) markets.
 🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Bramble Sharks (Echinorhinus brucus) caught in the deepwater shark liver oil fishery in India, stored in boxes after auction and en route to oil extraction plants. Photo by Ebeena Francis.

#PressRelease: Targeted deepwater shark liver oil fisheries are not sustainable. These fisheries have resulted in steep deepwater shark population declines and elevated extinction risk. 🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends #Overfishing
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Goblin Shark (Mitsukurina owstoni) caught as bycatch in a shrimp trawl fishery operating off Key West, Florida. Photo by Carl Moore/NOAA.

#SharksintheDark: Overfishing is the primary threat to deepwater sharks and rays. Most are caught as incidental capture of non-target species (bycatch). 🦑🌍🐟
 
#GlobalSharkTrends
bit.ly/SharksInTheD...
www.science.org/doi/10.1126/...

Deepwater sharks captured in a targeted deepwater shark liver oil fishery off the coast of Liberia. Photo by Melissa Romao/Sea Shepherd.

New analysis on #SharksintheDark funded by @SharkRayFund shows one in seven deepwater sharks and rays are threatened with extinction, more than twice the number reported a decade ago. 🦑🌍🐟

#GlobalSharkTrends
bit.ly/SharksInTheD...

Greenland Shark (Somniosus microcephalus). Photo by Andy Murch | www.sharksandrays.com

#PressRelease: Deepwater sharks are among the most sensitive marine vertebrates to overexploitation. Their biology is similar to formerly exploited, and now highly protected, marine mammals. 🦑🌍🐟
 
#SharksintheDark #GlobalSharkTrends
www.science.org/doi/10.1126/...